(self host 1/?): allow users to configure their own email service

[tefkah]

• feat: allow different email providers to be used when self-hosting, or allow users to disable email
• fix: handle errors and fix types

Issue(s) Resolved

Partially #954

Note

I will base the other self host prs on this one, but that does not mean we necessarily need to merge it!
If for some reason we do not want to allow users to use different email providers (?)

This allows users to pick a different email provider somewhat easily.

High-level Explanation of PR

Adds some documentation and presets on how to use different email providers with platfrom.

Additionally, this makes the MAILGUN_ env vars optional for self hosting. This will then only throw an error when you try to use the email client.
I don't want users to NEED to configure an email client. They should probably, but it should be possible to run one without.

I also considered adding an option to use the native sendmail or msmtp or equivalent, but I'm not sure we should encourage that.

Ideally I would have made this more typesafe by making our config a discriminated union, eg

z.object({ 
	SELF_HOST: z.literal("true"),
	MAILGUN_SMTP_HOST: z.string.optional(), 
// etc, all optional
}).or(z.object({
	SELF_HOST: z.undefined(),
	MAILGUN_SMTP_HOST: z.string()
	// etc, most required
}))

However this does not seem possible, so instead i have this weird wrapper

platform/core/lib/env/env.mjs

Lines 6 to 15 in c3bee15

	/**
	* Parameters which are optional if the app is self-hosted
	* but we do want checked for our AWS deploys
	*
	* @template {import("zod").ZodTypeAny} Z
	* @param {Z} schema
	*/
	const selfHostedOptional = (schema) => {
	return process.env.SELF_HOSTED ? schema.optional() : schema;
	};

Test Plan

1. Create an app password for your Google account
2. Configure the MAILGUN variables as such
   

   platform/self-host/README.md

   Lines 32 to 45 in 60758c9

   	#### GMail
   	To use GMail to relay emails through PubPub, you will need to create an [app password](https://support.google.com/accounts/answer/185833?hl=en).
   	You will be limited to 2000 emails per day by default this way.
   	```sh
   	MAILGUN_SMTP_HOST="smtp.gmail.com"
   	MAILGUN_SMTP_PORT=587 # or 465 for SSL
   	MAILGUN_SMTP_USERNAME="[email protected]"
   	MAILGUN_SMTP_PASSWORD="your app password" # this will be a 16 character string
   	MAILGUN_SMTP_FROM="[email protected]" # technically optional, but you will almost definitely need to set this.
   	MAILGUN_SMTP_FROM_NAME="Your Organization" # Optional, will default to "PubPub Team"
   	```

3. Send an email to a different email account than the one you configured
4. See it appear like magic

---

1. Also test the default mailgun config with the prod vars if possible (i do not have these i think)

Screenshots (if applicable)

Notes

the variables probably should not be prefixed by MAILGUN_, but i don't like messing with the terraform config.

[kalilsn]

Nice, though I do think we should drop the MAILGUN_ prefix. I can do it in a separate PR if you'd like since I don't mind messing with terraform

[kalilsn]

Might want to add this longer comment to the above "From" configs too. Though honestly I think we should make it and name required instead of having our defaults hardcoded.

[tefkah]

i agree. although i think this should be a community level config, not an installation wide one, which i why i left it for now

[kalilsn]

Yeah that sounds right to me! We shouldn't let people send arbitrary emails under our name 😟